Study On Dim Moving Target Detection Technique For Radar

With the rapid development of stealth technology and LPI radar, dim targets’detection has been a hot topic in the domain of modern radar. The common method ofdim moving target detection is to increase the signal to noise ratio via long-termintegration. In this dissertation, the Hough transform based on non-coherent integrationand the Keystone transform based on coherent integration are researched to detect thedim moving targets.Hough transform utilizes the idea of track before detection. By use of Houghtransform, the echo energy of a specific flight path can be effectively accumulatedthrough non-coherent integration, as makes the signal to noise ratio improved, which ispropitious to detect dim targets for radar. Firstly, the basic principle and signalprocessing flow of Hough transform are introduced in this thesis. The basic processingin the Hough parameter space is also researched. Then, the statistical performance ofHough transform is analyzed. Finally, the corresponding computer simulations aregiven.Keystone transform is the commonly used method to correct the range migration oftarget echo. By virtue of Keystone transform, the detection performance of radar is notrestricted to target’s movements, as makes a wide use in dim moving targets’ detectionwith long-term integration. The foundation of Keystone transform and the theoreticalcausation of range migration correction are researched in this thesis, with three practicalimplementation methods of Keystone transform being given. Finally, a generalizedKeystone transform algorithm is proposed, which makes the benchmark pulse ofKeystone transform controllable. Consequently, the system’s discrete time samplingerror is decreased, while the detection performance improved. Computer simulationsand real data processing results are given to confirm its validity.